package org.apache.commons.graph.algorithms.coloring

import org.apache.commons.graph.UndirectedGraph

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied.  See the License for the
* specific language governing permissions and limitations
* under the License.
*/

/**
 * Builder to specify the set of colors for coloring the graph.
 *
 * @param <V> the Graph vertices type
 * @param <E> the Graph edges type
</E></V> */
interface ColorsBuilder<V, E> {
    /**
     * Specifies the set of colors for coloring the graph.
     *
     * @param <C> the Color type.
     * @param colors the set of colors for coloring the graph.
     * @return the coloring algorithm selector.
    </C> */
    fun <C> withColors(colors: Set<C>): ColoringAlgorithmsSelector<V, E, C>
}


/**
 * [ColorsBuilder] implementation
 *
 * @param <V> the Graph vertices type
 * @param <E> the Graph edges type
</E></V> */
/**
 * Creates a new instance of [DefaultColorsBuilder] for the input graph.
 * @param graph the graph
 */
class DefaultColorsBuilder<V, E>(
    private val graph: UndirectedGraph<V, E>
) : ColorsBuilder<V, E> {
    /**
     * {@inheritDoc}
     */
    override fun <C> withColors(colors: Set<C>): ColoringAlgorithmsSelector<V, E, C> {
        //var colors = colors
        //colors = Assertions.checkNotNull(colors, "Colors set must be not null")
        return DefaultColoringAlgorithmsSelector(
            graph,
            colors
        )
    }
}

fun <V, E, G : UndirectedGraph<V, E>> G.coloring(): ColorsBuilder<V, E> =
    DefaultColorsBuilder(this)

fun <V, E, G : UndirectedGraph<V, E>,C> G.coloring(colors: Set<C>) = coloring().withColors(colors)

//fun <V, E, G : UndirectedGraph<V, E>,C> G.coloring(vararg colors: C) = coloring(colors.toSet())
